Thiamin Biosynthesis in Saccharomyces cer-evisiae ORIGIN OF CARBON-2 OF THE THIAZOLE MOIETY By ROBERT L. WHITE and ]AN D. SPENSER
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چکیده
Although the structure of thiamin (vitamin B,) has been known for over 40 years (Williams, 1936; Grewe, 1936) and its chemical synthesis accomplished soon thereafter (Williams & Cline, 1936; Andersag & Westphal, 1937; Todd & Bergel, 1937), the biosynthetic pathway to thiamin (3) has still not been elucidated completely. It is well established that the pyrimidine (1) and thiazole (2) moieties are biosynthesized independently and are then joined to give thiamin (Scheme 1) (Leder, 1975). However, there is no general agreement concerning the basic
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